1 files changed, 31 insertions, 8 deletions

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 98a7111dd53f..a4fee1e4fdda 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2086,15 +2086,38 @@ static int ufshcd_read_desc_param(struct ufs_hba *hba,
 					desc_id, desc_index, 0, desc_buf,
 					&buff_len);
 
-	if (ret || (buff_len < ufs_query_desc_max_size[desc_id]) ||
-	    (desc_buf[QUERY_DESC_LENGTH_OFFSET] !=
-	     ufs_query_desc_max_size[desc_id])
-	    || (desc_buf[QUERY_DESC_DESC_TYPE_OFFSET] != desc_id)) {
-		dev_err(hba->dev, "%s: Failed reading descriptor. desc_id %d param_offset %d buff_len %d ret %d",
-			__func__, desc_id, param_offset, buff_len, ret);
-		if (!ret)
-			ret = -EINVAL;
+	if (ret) {
+		dev_err(hba->dev, "%s: Failed reading descriptor. desc_id %d, desc_index %d, param_offset %d, ret %d",
+			__func__, desc_id, desc_index, param_offset, ret);
+
+		goto out;
+	}
+
+	/* Sanity check */
+	if (desc_buf[QUERY_DESC_DESC_TYPE_OFFSET] != desc_id) {
+		dev_err(hba->dev, "%s: invalid desc_id %d in descriptor header",
+			__func__, desc_buf[QUERY_DESC_DESC_TYPE_OFFSET]);
+		ret = -EINVAL;
+		goto out;
+	}
 
+	/*
+	 * While reading variable size descriptors (like string descriptor),
+	 * some UFS devices may report the "LENGTH" (field in "Transaction
+	 * Specific fields" of Query Response UPIU) same as what was requested
+	 * in Query Request UPIU instead of reporting the actual size of the
+	 * variable size descriptor.
+	 * Although it's safe to ignore the "LENGTH" field for variable size
+	 * descriptors as we can always derive the length of the descriptor from
+	 * the descriptor header fields. Hence this change impose the length
+	 * match check only for fixed size descriptors (for which we always
+	 * request the correct size as part of Query Request UPIU).
+	 */
+	if ((desc_id != QUERY_DESC_IDN_STRING) &&
+	    (buff_len != desc_buf[QUERY_DESC_LENGTH_OFFSET])) {
+		dev_err(hba->dev, "%s: desc_buf length mismatch: buff_len %d, buff_len(desc_header) %d",
+			__func__, buff_len, desc_buf[QUERY_DESC_LENGTH_OFFSET]);
+		ret = -EINVAL;
 		goto out;
 	}